#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>

int main() {
    int a, b, c;
    scanf("%d%d%d", &a, &b, &c);
    int sum = (a * 0.2) + (b * 0.3) + (c * 0.5);
    printf("%d", sum);
    return 0;
}